
function s1_generate_a_series_of_files(){

  for i in {1..100};do
    
	echo $i > /tmp/new_file$i;done
} 
function s2_list_4_files_in_long_format_about_account_and_group(){
   ls -l /etc/{passwd,shadow,group,gshadow} |sort -d
}
function s3_find_items_related_to_given_username(){
 grep -h $1 /etc/{passwd,shadow} |sort -d
}
function s4_find_items_related_to_given_group_name(){
   
   grep -h $1  /etc/{group,gshadow} |sort -d
}
function s5_create_groups_for_given_group_name(){
     groupadd rnd && groupadd itoperation
}
function s6_create_users_and_set_their_group_as_required(){
  useradd -G rnd adam && useradd -G rnd bob && useradd -G itoperation calvin &&
  useradd -G itoperation david && useradd -G rnd edward
}
function s7_change_users_shell(){
   usermod -s /usr/bin/sh adam && usermod -s /usr/bin/sh edward
}
function s8_set_password_change_policy(){
  chage -m 10 -M 60 -W 10 adam
chage -m 10 -M 60 -W 10 bob
chage -m 10 -M 60 -W 10 calvin
chage -m 10 -M 60 -W 10 david
chage -m 10 -M 60 -W 10 edward
}
s9_set_password_for_five_users(){
if ["$#" -ne 5 ]; then
    echo "error"
    exit
fi
usernames=("adam" "bob" "calvin" "david" "edward")
for i in {0..4}; do
echo "${usernames[$i]}:$(printf "%s" "$1" "$2" "$3" "$4" "$5" | awk -v
n=$i '{print $n}')"
done | chpasswd
echo "Ture"
}
function s10_lock_bobs_password(){
    usermod -L bob
}
function s11_include_adam_into_wheel_group(){
    usermod -a -G wheel adam  
}
function s12_change_files_permission(){
   for i in {1..33};do chmod -R 640 /tmp/new_file$[3*i];done
}


